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The aim of this work was to use electrospray to create photocatalytic TiO 2 coatings and to study their antibacterial and antibiofilm capacity. The electrospray used a sol of TiO 2 anatase nanoparticles prepared by a sol–gel method, which formed stable suspensions of positively charged particles (ζ-potential + 22.3 ± 3.7 mV). The electrospray deposited TiO 2 on non-porous glass surfaces at two loading densities originating homogeneous coatings (3.2–4.3 µm) of particles the top layer of which displayed aggregates ranging from the micron scale to a few hundreds of nanometers, with lower size as TiO 2 loading increased. TiO 2 -functionalized surfaces were tested for the inactivation of the Gram-positive bacterium Staphylococcus aureus . The electrosprayed surface was moderately hydrophilic turning highly hydrophilic upon irradiation (water contact angle 9.6° after 15 h under Xe-arc lamp). photocatalytic surfaces were put in contact with exponentially growing bacterial cultures in a flow system in which solar simulated irradiation followed two different 24 h dark-light arrangements with 9 or 18 h dark exposure followed by 15 or 6 h irradiation. The electrosprayed surfaces experienced extensive colonization by viable bacteria and clear biofilm formation revealed by exopolysaccharide matrix visualization. Using both dark-light cycles all cells became non-viable with extensive membrane damage. Biofilm matrix measurements showed that the irradiated surfaces were essentially free of bacterial exopolysaccharide matrix for specimens with the higher TiO 2 loading density. The biofilm removal reached 99% and no regrowth of viable cells was observed in any case. The results showed that TiO 2 -electrospray can avoid biofilm accumulation under stringent environmental conditions. [ABSTRACT FROM AUTHOR]